package org.knowm.xchange.huobi.service; import java.io.UnsupportedEncodingException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.List; import java.util.Map; import java.util.Map.Entry; import javax.ws.rs.FormParam; import si.mazi.rescu.Params; import si.mazi.rescu.ParamsDigest; import si.mazi.rescu.RestInvocation; public class HuobiDigest implements ParamsDigest { private static final char[] DIGITS_LOWER = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; private final String secretKey; private final String secretKeyDigestName; private final MessageDigest md; private final Comparator<Entry<String, String>> comparator = new Comparator<Map.Entry<String, String>>() { @Override public int compare(Entry<String, String> o1, Entry<String, String> o2) { return o1.getKey().compareTo(o2.getKey()); } }; public HuobiDigest(String secretKey, String secretKeySignatureName) { this.secretKey = secretKey; this.secretKeyDigestName = secretKeySignatureName; try { md = MessageDigest.getInstance("MD5"); } catch (NoSuchAlgorithmException e) { throw new RuntimeException("Problem instantiating message digest."); } } private static char[] encodeHex(byte[] data, char[] toDigits) { int l = data.length; char[] out = new char[l << 1]; // two characters form the hex value. for (int i = 0, j = 0; i < l; i++) { out[j++] = toDigits[(0xF0 & data[i]) >>> 4]; out[j++] = toDigits[0x0F & data[i]]; } return out; } @Override public String digestParams(RestInvocation restInvocation) { final Params params = restInvocation.getParamsMap().get(FormParam.class); final Map<String, String> nameValueMap = params.asHttpHeaders(); nameValueMap.remove("sign"); nameValueMap.put(secretKeyDigestName, secretKey); final List<Map.Entry<String, String>> nameValueList = new ArrayList<Map.Entry<String, String>>(nameValueMap.entrySet()); Collections.sort(nameValueList, comparator); final Params newParams = Params.of(); for (int i = 0; i < nameValueList.size(); i++) { Map.Entry<String, String> param = nameValueList.get(i); newParams.add(param.getKey(), param.getValue()); } final String message = newParams.asQueryString(); try { md.reset(); byte[] digest = md.digest(message.getBytes("UTF-8")); return String.valueOf(encodeHex(digest, DIGITS_LOWER)); } catch (UnsupportedEncodingException e) { throw new RuntimeException("Codec error", e); } } }